1. Field of the Invention
This invention relates to a storage device system, which has a storage device of a first standard having a first mainframe volume, and a storage device of a second standard more advanced than the above first standard, having a second mainframe volume and connected via the interface of an open system to the above first-standard storage device.
2. Description of the Related Art
In the prior art, storage control devices have been proposed which enable sharing in each storage media among host computers (HCPs) having various different host computer input/output interfaces. In such a storage control device, when there is a write request from an HCP, the control processor references a host computer interface management table, and if the HCP data format is an open-system FBA format, writes the write data without modification to a cache slot in cache memory, but if the format is a mainframe CKD format, performs conversion into FBA format and writes the data. When there is a read request from an HCP, the control processor references the host computer interface management table, and if the HCP data format is FBA, transfers the data read from the cache slot to the HCP without modification, but if the format is CKD, performs conversion into FBA and transfers the data. Another control processor searches for write data in cache memory and performs writing to a drive (see for example Japanese Patent Laid-open No. 9-325905).
FIG. 1 is a block diagram showing in summary a storage system of the prior art.
In the storage system shown in FIG. 1, when the mainframe host computer (MF host) 1 transmits a read/write command to the storage device 3 via a channel interface (channel I/F) and communication port, a channel adapter (CHA) 5 in the storage device 3 receives the read/write command. As a result, read/write processing is executed in the storage device 3. In the storage device 3, mainframe data (MF data) is stored in a logical device (logical volume) (LDEV B) 7. The LDEV B7 is created on the physical devices (physical volumes) (PDEV B) 91, 92, 93, 94, and the LDEV B7 is mapped to a RAID (Redundant Array of Independent Inexpensive Disks) configuration of the plurality of PDEV B devices 91, 92, 93, 94.
However, when a user newly introduces a storage device based on a high standard and comprising superior functions such as, for example, data protection functions, upon using this high-standard storage device, all the data stored in the storage device 3 must be transferred to the above high-standard storage device (data migration). However, there is the problem that this data migration task entails a large amount of labor. Further, in addition to the above task, after data has been migrated the storage device 3 must be disconnected from all connected hosts, and these hosts must be newly connected to the above high-standard storage device. Moreover, situations may arise in which, even though the storage device 3 can still be used effectively by some users, the storage device 3 is discarded simply because it is an older model, so that information processing resources are wasted.